Horror cinema doesn’t get any more notorious than Ruggero Deodato’s Cannibal Holocaust. As widely discussed as anything in the genre it still utterly divides audiences and although certain elements seem of their era, it packs a punch that has rarely been topped since. Although clearly part of the Italian cannibal cycle that began in the early seventies with Umberto Lenzi’s Deep River Savages and continued for another decade, offering such dubious delights as Prisoner of the Cannibal God, Eaten Alive and Cannibal Ferox, Cannibal Holocaust tops them all on every level – both in its intelligence and technique, and sheer unrelenting nastiness.

The film is divided into two sections, the first more conventional than the second. A TV network commission a quartet of award-winning documentary makers to head into the Amazonian jungle to film the natives there, but they don’t return. So respected anthropologist Harold Monroe (Robert Kerman) is sent out after them to see if he can discover what has happened – the trail leads to the cannibalistic Yamamoto tribe, where he finds their skeletal remains. The tribe are wary of their Western visitor but are transfixed by the apparent magical properties of his dictaphone, and Monroe is able to leave with the rolls of film that the quartet shot before meeting a sticky end. This first 40 minutes or so is filmed as a straight adventure yarn – albeit one peppered with extreme sexual violence and real-life animal cruelty – but even this section contains a surprisingly gripping realism largely absent elsewhere in the genre. It’s not that it’s all that well acted (Robert Kerman is also known as porn star Richard Bolla) or even filmed (Deodato is as zoom-happy as any of his Italian filmmaking contemporaries), but there’s a chilling inevitability to Monroe’s journey and his eventual discovery of the team’s remains.

It is the second section that really gets the film its reputation. Monroe returns to New York, and insists he reviews the footage before it is broadcast by the TV company, and so he – and us – sit down to watch exactly what the team shot. Comprising director Alan Yates, his girlfriend Tina and cameramen Jack and Mark, we quickly see that the team have no interest in anything other than sensationalism and furthering their reputations as maverick filmmakers, and will go to shocking lengths to create controversial footage. This is hinted at by the clips of an earlier film they made ‘The Long Road Back To Hell’, in which Yates paid a South American army to fake executions, but here, amongst people they consider to be little more than animals, their savage duplicity runs amok. A native village is set on fire, animals (turtle, muskrat, monkeys and a pig) are killed in graphic detail, a woman is viciously gang raped by the three men, and then cruelly put to death by her fellow tribes people. Even when the Yamamotos turn on the filmmakers, the cameras keep rolling.

Deodato nails the mock-documentary technique with a perfection that had rarely been seen either within or outside the horror genre, using only footage shot on the two handheld 16mm cameras and placing scratches, light blemishes and jump cuts on the film stock. This is the main reason why this section of the film is so effective – of course we know the atrocities committed by Alan and his crew and upon the natives (and vice versa) are faked, but there is a realism and immediacy to them that is shocking. And of course, the treatment that Deodato and co dish out to animals IS real. Animal cruelty has always been the most distasteful, almost entirely indefensible element of these films, but there is little denying that its inclusion adds to the savage, uncompromising tone.

Throughout this last section of the film, the film cuts back to an increasingly horrified Monroe in New York, who is reviewing the footage. The TV company are adamant about showing it, but they quickly change their minds after he shows them the final reels that the team shot before their untimely demises. Monroe is the film’s ‘conscience’ and his final line: "I wonder who the real savages are" has been much debated over the years. It is certainly an obvious, heavy-handed line, but nevertheless succeeds in implicating everyone in the film – the characters, the filmmakers and the viewers themselves. Cannibal Holocaust is a film that will continue to divide audiences – I’m not even sure how much I like it, and for all its intelligence and technical verve it is still an exploitative, nasty and perhaps hypocritical film. But if part of cinema’s role is to challenge and disturb, then this film remains an undeniably important piece of film history.

Italian director best known his ultra-violent horror work, but whose filmography takes in many genres over a 40-year career. Worked as an assistant director on a variety of films during the sixties, and made his first credited directing debut in 1968 with the superhero yarn Phenomenal and the Treasure of Tutankamen. Throughout the following decade Deodato made erotic dramas (Gungalar, Waves of Lust), musical comdies (Man Only Cries for Love), and comic book romps (Zenabel).

It was Ruggero's horror films that gained him an international reputation however. The trashy Last Cannibal World was followed by 1980's notorious Cannibal Holocaust, and the likes of House on the Edge of the Park, Cut and Run and Bodycount were popular amongst video audiences during the eighties. Other films during this period include the action fantasy The Barbarians and bizarre thriller Dial Help, while Deodato's work during the nineties was largely confined to Italian TV.